The Expression Profiling of the Lipoxygenase (LOX) Family Genes During Fruit Development, Abiotic Stress and Hormonal Treatments in Cucumber (Cucumis sativus L.)

Abstract

Lipoxygenases (LOXs) are non-haem iron-containing dioxygenases that catalyse oxygenation of polyunsaturated fatty acids and lipids to initiate the formation of a group of biologically active compounds called oxylipins. Plant oxylipins play important and diverse functions in the cells. In the current study, expression analysis during cucumber development using semi-quantitative RT-PCR revealed that 13 of 23 CsLOX genes were detectable, and were tissue specific or preferential accumulation. In total, 12 genes were found to be differentially expressed during fruit development and have different patterns of expression in exocarp, endocarp and pulp at day 5 after anthesis. The expression analysis of these 12 cucumber LOX genes in response to abiotic stresses and plant growth regulator treatments revealed their differential transcript in response to more than one treatment, indicating their diverse functions in abiotic stress and hormone responses. Results suggest that in cucumber the expanded LOX genes may play more diverse roles in life cycle and comprehensive data generated will be helpful in conducting functional genomic studies to understand their precise roles in cucumber fruit development and stress responses.

Optimal hypobaric treatment delays ripening of honey peach fruit via increasing endogenous energy status and enhancing antioxidant defence systems during storage

“…This result was in agreement with the maintenance of membrane integrity in green asparagus via the three-storage hypobaric treatment described by Li et al (2008). The LOX pathways play a key role in membrane deterioration and peroxidation of polyunsaturated fatty acids, and they participate in fruit development and ripening (Yang et al, 2012). Loss of membrane integrity may in turn result in the release of LOX enzymes that could further promote degradation and peroxidation of membrane lipids (Maalekuu et al, 2006).…”

Leaf Volatile Compounds and Associated Gene Expression during Short-Term Nitrogen Deficient Treatments in Cucumis Seedlings

“…LOX proteins and their metabolites have been demonstrated to involve in production of short-chain volatile compounds [11] and plant defense responses during various stresses [24,25]. To study the effect of nitrogen deficiency on the biosynthesis of volatiles in cucumber seedlings, LOX gene expression profiles in cucumber leaves were analyzed by qPCR.…”

“…Plants produce volatile compounds, such as C6 aldehydes, C9 aldehydes, and their acetates, through the lipoxygenase (LOX) and hydroperoxidelyase (HPL) pathways [9]. Linoleic and α-linolenic acid are the substrates for dioxgenation and subsequent cleavage to obtain C6 and C9 volatile aldehydes, which can be further modified by alcohol dehydrogenases (ADH) [10,11]. ( E , Z )-2,6-nonadienal (which has a cucumber-like flavor) and ( E )-2-hexenal (which has an apple-like flavor) are the main volatile compounds [8,12].…”

Lipoxygenases and their metabolites in formation of plant stress tolerance

“…Gene LoX expression was found to occur under low temperature conditions that is an indirect indicative of LOX involvement in the formation of plant adaptive responses to temperature stresses [105]. LOX enzyme activity increase resulting from low temperature effects is associated with phospholipase D which activity enhances due to stress factor action and that promotes membrane phospholipids degradation and release of PUFA -LOX substrate [106].…”